defrag your hard drive, and use disk cleanup to cleanup unnecessary files on your comp.
also, do a complete antivirus scan with updated and proper antivirus software.
uninstall unnecessary programs on your comp.
Also, use windows update to update your comp, and install everthing it provides you with(including the optional updates)
if everything on your comp is like what you said, then it shouldn't be choppy unless there is a virus, some RAM/processor/hard drive hog, your hard drive is too cluttered with unnecessary files or the files required for your h2v are too fragmented all over the hard drive (ie. some sections of all the files spread all over the place, so it would take a lot longer for your hard drive to access them).
for more info on what I mean, look here:
hope this helps.Edited by sargejohnson on Oct 3, 2009 at 10:24 AM